displaying results and hiding duplicates - php

Question

I have a list of catagores found at the bottom of THIS PAGE
this code:
<?php
include_once('include/article.php');
$article = new article;
$articles = $article->fetch_all();
?>
<?php foreach ($articles as $article) { ?>
<div id="content">
<a href="list.php?id=<?php echo $article['promo_cat']; ?>">
<li class="button"><ul class="pageitem">
<?php echo $article['promo_cat']; ?>
</li></ul></div>
</a>
<?php } ?>
displays the value of the promo_cat field in my mysql table as a list:
as you can see. there are 2 "FREE" fields. How do I edit this code so that it does not show up any duplicates?
I understand that I need to use a DISTINCT feature but im not sure how to. Please help.
thank you.
If you require any more coe from another page then please ask and I will edit this post and add it.

Answer 1

SELECT DISTINCT `promo_cat` FROM mobi WHERE `something` = 'something'
More on DISTINCT from http://forums.mysql.com/

Answer 2

for future reference.
changing my above code to:
<?php
include_once('include/article.php');
$category = new category;
$articles = $category->fetch_all();
?>
<?php foreach ($articles as $article) { ?>
<div id="content">
<a href="list.php?id=<?php echo $article['promo_cat']; ?>">
<li class="button"><ul class="pageitem">
<?php echo $article['promo_cat']; ?>
</li></ul></div>
</a>
<?php } ?>
and adding a new CLASS to my /include/article.php that reads:
class category {
public function fetch_all(){
global $pdo;
$query = $pdo->prepare("SELECT DISTINCT `promo_cat` FROM mobi");
$query->execute();
return $query->fetchAll();
}
public function fetch_data($promo_cat) {
global $pdo;
$query = $pdo->prepare("SELECT DISTINCT * FROM mobi WHERE `something` = 'something'");
$query->bindValue(1, $promo_cat);
$query->execute();
return $query->fetch();
}
}
Fixed my problem.
thank you.